I am looking at purchasing a new desktop computer. Still have not gone 100% with the imac over the pc.
I would like some help determining for my needs which one is a better buy.

I will need to run a windows operating system I guess with parallels for my online poker. Some of the software needs windows to run.

So my plan is to have dual monitors, one running the windows with all of my poker windows(4-8windows + poker tracker program) and the other monitor to be used for web surfing, watching videos or movies,photoshop,etc at the same time.

Best machine for you would be a Windows computer.
Seems like the majority of your software/uses would require Windows, so you don't seem like you'll benefit from getting a Mac.

mac: a waterproof raincoat made of rubberized fabric
MAC: a data communication protocol sub-layer, also known as the Media Access Control
Mac: a brand name which covers several lines of personal computers designed, developed, and marketed by Apple Inc.